the Economy of the Strepsiptera. 165 



could not discover any mandicatory organs in the larva : and reared 

 as many as twenty specimens, all of which had similarly formed ab- 

 domens and antennae. 



Messrs. Kirby and Spence, in their ' Introduction to Entomology', 

 state that this order consists of two genera, Xenos and Stijlops ; since 

 the publication of which Mr. Curtis has published two others, 

 Halictophagus and Elenchus. Messrs. K. and S. further add that 

 the eggs of the Sty lops appear to be deposited in the abdomens 

 of the Melittce, on which the larvae feed till, having attained their 

 full growth, they perforate the membrane that connects its seg- 

 ments, and at the proper time their pupa-case bursts, they emerge, 

 and take their flight. 



From the preceding quotations we are enabled to perceive that 

 the real extent of the knowledge obtained relative to the eaxdier 

 stages of the life of the Strepsiptera only amounts to this, viz. 

 that according to the statements of Messrs. Jurine and Peck the 

 larvae of these insects had been found entirely within the abdomens 

 of the perfect wasp ; but as regards the deposition of the egg, the 

 suppos'.tions of the different authors are much at variance, some 

 sayinr^ that it is in the larva, others in the perfect insect, that the 

 parasite lays its egg. Therefore the points in the economy of the 

 Strepsiptera respecting which information or confirmation is re- 

 quired may be arranged as follows. 



1 . "What are the sexual distinctions in these insects ? 



2. In what manner and at what period of the year does the fe- 

 cundation of the female take place .'' 



3. At what period of the year are the eggs deposited ? 



4. Are they deposited separately in the cell of the wasp or bee, 

 or are they laid in the eggs of those insects, or within the larva, 

 pupa, or perfect insect ? 



5. How long do they remain unhatched, and do they lie in that 

 state until the larva of the insect attacked has attained its full 

 growth, or assumed the pupa state ? 



6. How long do the larvae of the Strepsiptera remain in that state .-' 

 Do they cast their skins ? In what manner do they feed } 



7. How long do they remain in the pupa state ? 



8. Do the parasites render abortive the female Hymenoptera, in 

 the bodies of which they are reared } 



9. Do the sexes appear simultaneously? 



10. Do the perfect Strepsiptera take any nutriment } 



11. Of what use are those acute organs termed mandibles, and 

 the two -jointed palpi .'' 



12. What genera of bees are attacked in this country.'* 



VOL. I. PART III. o 



